The present invention relates to an apparatus for heating food products, particularly proteinaceous food, such as hamburger patties. More particularly, the apparatus of the invention pertain to rapidly and efficiently cooking such products in fast food service restaurants.
Depending on how they are cooked, hamburgers are delicious, succulent food, and as a result, many restaurants all across the country specialize in serving this singular menu item. It is well known that the ingredients which contribute to the unique taste of hamburger are the fats and meat juices. Beef tallow, however, has a relatively low solidification point within the range of 88.degree.-100.degree. F. and, therefore, hamburgers are preferably formed into relatively thick patties and cooked at relatively low temperatures to prevent the tasty fats and meat juices from being melted or boiled away. Nonetheless, for reasons explained more fully hereinafter, fast food restaurants have found it commercially expedient to use relatively thin patties and cook them at relatively high temperatures in order to reduce the preparation time.
At the present time there are a wide variety of fast food restaurants which sell hamburgers and similar food items. Necessary to the success of such fast food operations is the ability to rapidly cook, garnish and serve hamburgers. It has become an accepted practice in the fast food industry to roll or press hamburgers into relatively thin patties, usually less than 1/4", in order to decrease the amount of time necessary to cook them thoroughly. In particular, it has been found that by reducing the thickness of the hamburger patties, the distance the heat must travel through each patty is reduced, thereby reducing the amount of time necessary to cook the meat.
Though tastes differ, it has been found that the interior of a 1/4 lb. hamburger patty must be heated to a temperature of 140.degree. to 170.degree., which temperature must be sustained for 25 seconds before the patty is considered sufficiently done. To rapidly achieve this interior temperature, the exterior surfaces of the hamburger patty are subjected to relatively high temperatures, generally between 325.degree. and 600.degree. F. For example, by conventional means it will take 150 seconds to cool a 1.6 oz. hamburger. The large majority of this time, 125 seconds, is used to heat the patty up to the flavor cooking temperature range (140.degree. to 170.degree. F.). The remaining 25 seconds actually cooks the interior of the patty. Establishments which cook hamburgers in this manner sometimes utilize an open griddle which is operated by at least one attendant. As such, relatively large amounts of heat energy and a relatively large amount of manpower is required to prepare hamburgers in this manner.
During cooking on an open grill there is a tendency for the hamburger patty to crawl together, shrink in diameter, and become thick in the center. This not only creates an undesirable appearance, it also creates cooking problems because the increased thickness requires higher temperatures, longer cooking time, or both. Increasing the cooking conditions tends to reduce the amount of fat and juices in the patty so that there is not only a weight loss, but the product also tends to have a dry taste.
A popular alternative to the grill method of preparing hamburgers is the use of a broiler having heating elements inside a cabinet or hotbox. A chain conveyor carries the hamburger patties through the hotbox, and by adjusting the speed of the conveyor, the thickness of the hamburger patties, and the temperature of the heating elements, the hamburger patties can be rapidly cooked to the desired temperatures with minimal supervision. The temperatures of the heaters used in hotboxes of the type described varies between 350.degree. F. and 700.degree. F., but since the heaters can be disposed above and below the chain conveyor, the hamburger can be heated on both sides simultaneously, or consecutively. As a result, hamburgers are cooked by the broiler method in approximately half of the time normally required by the grill method, and with a minimal amount of manpower.
Though the broiler method of cooking hamburgers is successfully used in fast food restaurant operations, it is also subject to numerous drawbacks. There are a number of variable conditions in the broiler which as a practicable matter must remain fixed; namely, speed of the conveyor and the temperatures of the heaters; and this has disadvantages. For example, it is commercially impractical to cook hamburgers of both thin (1/4 inch) and thick (3/4 inch) sizes by the broiler method because that necessitates changing cooking conditions which is impractical.
Most importantly, both the grill method and the broiler method of cooking hamburgers rely on the relatively slow process of heat conduction through the hamburger patty itself. Thus, while one must wait for the interior of the hamburger patty to reach the flavor cooking temperature range (140.degree.-170.degree. F.), the exterior portions are being directly exposed to relatively high temperatures for up to 150 seconds. During this period of time, the fats and meat juices located near the more exterior portions of the hamburger patty are melted or boiled away, causing a noticeable loss of taste. In addition, a substantial amount of shrinkage results, a factor of increasing importance in an era of burgeoning meat prices.
For all these reasons, the hamburger prepared in fast food operations is often characterized by relatively thin, shriveled patties having a bland taste. In contrast to the hamburgers prepared in fast food restaurants, the hamburgers prepared in the home, where high speed preparation is not of the essence, are often thicker, juicier, and tastier. The primary reason for this difference is that hamburgers prepared at home can be cooked slowly at lower temperatures. The relatively long period of time required to produce such a product is wholly impractical for fast food operations, and therefore, compromise in taste and thickness must be made.
Accordingly, it is a primary object of this invention to provide an improved apparatus for rapid, efficient, and economical heating of food products, such as hamburger patties, as may be preformed in fast food service restaurants.
It is another object of this invention to provide a relatively compact, automated appliance for promoting the rapid cooking of food products of the type normally shaped into patties.
It is a further object of this invention to provide a mobile appliance for impaling and holding a quantity of food, and carrying said quantity of food through a broiler.
It is still a further object of this invention to provide an apparatus for rapidly cooking proteinaceous food, particularly hamburgers, with a minimal amount of heat energy and at a minimal temperature.
A still further object of this invention is to provide improved means for rapidly, and substantially uniformly, transferring heat throughout the interior of a quantity of food, particularly hamburgers.
Still another object of this invention is to provide improved means for rapidly cooking a relatively thick hamburger patty with a minimal amount of heat energy.
Still another object of this invention is to provide an appliance, having a plurality of projecting grills extending therefrom, for impaling and holding a quantity of proteinaceous food, and carrying said quantity of food through a broiler, and passing heat substantially uniformly from the broiler, through the projecting grills, to the interior of the food impaled and held thereon.
Still another object of this invention is to provide an improved apparatus for removing a quantity of food impaled and held on an appliance.
Still another object of this invention is to provide an improved apparatus for engaging and disengaging a hot appliance, having a plurality of projections extending therefrom, used for impaling and holding a quantity of food.
Still another object of this invention is to provide an improved means for cooking proteinaceous food patty, particularly hamburgers by rapidly bringing the interior of the such patty rapidly to cooking temperatures in the range from 140.degree. F. to 170.degree. F.
Still another object of this invention is to provide an improved means for carrying food through a broiler.
Still another object of this invention is to provide an improved means for rapidly cooking a quantity of proteinaceous food.
Still another object of this invention is to interiorily place all heated surfaces so as to entrap virtually all cooking heat and odors, thus reducing heating energy required in the cooking process by more than 75%.
Other objects, features and advantages of this invention will become apparent upon reading the following detailed description in conjunction with the accompanying drawings.